Incandescent electric lamp



(-No Model.) 2 Sheets-Sheet 1. A. L. REINMANN. INOANDESGENT ELECTRICLAMP.

No. 434,159. Patented Aug. 12, 1890.

2 sheets sheet 2.

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I a d 0 M 0 W v PatentedAug. 12,1890.

Fianfi'- wine-sway,

. UNITED STATES,

To all whom it may concern:

Be it known that I, ALBERT L. REINMANN,

a citizen of the United States, residing in Allegheny city, in thecounty of Allegheny and State of Pennsylvania, have invented a new anduseful Improvement in Bottoms for Incandescent-Electric-Lam p Bulbs,(Case No. 316,) of which the following is a specification.

The invention relates to the construction IO of bottoms forelectric-lamp bulbs, and involves certain details in the construction ofthe same. P The invention consists in certain improvements in theformation of the shell and of the 15. contact-plug, as will be moreparticularly described hereinafter.

The invention will be described in detail in connection with theaccompanyimg drawings, in which Figure 1 is a section of thelamp-bottom. Fig. 2is a plan of the interior of the bottom, and Fig. 3is a plan of the exterior of the bottom. Fig. 4 is an enlarged sectionshowing the neck of the bulb in position, and Fig. 5 is an elevation ofthe same.

Referring to the drawings, A represents the main portion of the bottom,which usui ally consists of a shell of metal, preferably brass orsimilar material. A bottom plate b,

of insulating or non-conducting material, is fastened in the bottom ofthis shell, this plate carrying at its center a contact-point c. Theshell is constructed with a circular rib (l, which is designed to beengaged by a corresponding E 3 5 bead on the ends of the arms of thesocketin a manner well understood. The shell also has a circularindentation or bead e, which serves as a shoulder against which thebottom plate I) rest-s. The end of the shell receiving the bulb ispreferably expanded, as shown atf, for the purpose of receiving the neckof the lamp-bulb. The end of the shell is turned or spun over the bottomplate after it has been inserted, thereby holding it in 5 place.

The bottom plate I) is constructed with a central opening h forreceiving the central contact-pin it. This is inserted through theopening, and its inner end is upset upon a washer It" for holding thepin firmly. The bottom plate is also provided with a groove PATENTOFFICE.

ALBERT L. REINMANN, OF ALLEGHENY, ASSIGNOR TO TIIE WESTINGHOUSE ELECTRICCOMPANY, OF PITTSBURG, PENNSYLVANIA.

INCANDESCENT ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 434,159, dated August12,1890. Application filed November 14, 1889- Serial No. 330,262. (Nomodel-1 m at its side, gradually narrowing from the inner side to theouter, through which one of the leading-in wires of the lamp is led.This outer end of the pin, whichis for this pur- 6o pose made concave,as shown at 1).

The portion of the neck of a lamp-bulb which is surrounded by the bottompiece or cup usually becomes very hot by reason of the heat developed inthe leading-in wires and in the filament, and as the neck of the lamp isusually fastened into the shell by a cement, as shown at s, the shell isclosed and the heat is confined. In consequence the bottom or neck ofthelampbulb isliable to crack. 7c By providing ventilation at this pointthis danger is materially lessened, This is accomplished by formingopenings 0" through the shell. These may be conveniently formed bystriking the metal inward, leaving the lips 17 projecting immediatelyabove the bottom plate, or by striking out small pieces of the metal orperforating the shell. These openin gs afford ventilation and allow thecirculation of the air around the neck of the lamp after it has beenplaced in the bottom, thereby lessening the liability of the lamp tocrack at the point where the leading-in wires enter the bulb.

I claim as my invention 1. In a lamp-bottom, the combination of a shelland bottom plate of insulating material, said shell having a grooveformed in its edge for receiving a leading-in wire, substantially asdescribed.

2. In a lamp-bottom, the combination, with a plate of insulatingmaterial, of a hollow or perforated contact-plug for the purpose ofreceiving the leading-in wire having a concave or indented end,substantially as described. 95

In testimony whereof I have hereunto subscribed my name this 9th day ofNovember,

- ALBERT L. REINMANN.

Witnesses:

J. W. SMITH,

A. O. DETOHON.

